Cement Calculator
Accurate cement estimator for all your projects. Use our cement calculator in feet to find exact bag counts and yardage.
Quick Reference Rules of Thumb:
- For M20 concrete: approximately 8 bags of 50kg cement per 1m
- For standard mortar (1:4): approximately 5 bags of 50kg cement per m at 10mm depth
Project Dimensions
Materials Required
For estimation purposes only. Verify structural calculations with a licensed engineer.
Cement Calculator vs Concrete Calculator
In the construction industry, people use the terms "cement" and "concrete" interchangeably. Therefore, when someone searches for a cement calculator for slab or a cement calculator in feet, they usually want to know how much pre-mixed concrete to buy.
The Big Difference: Cement is merely an ingredient. Portland cement is the ultra-fine gray powder that binds everything together. Concrete is the final, rock-hard building material that results from mixing cement, water, sand, and gravel.
Our cement calc functions primarily as a concrete volume estimator. It allows you to calculate total cubic feet, total cubic yards, and the exact number of 80lb, 60lb, or 40lb pre-mixed bags you need at the hardware store.
How to Use a Cement Calculator in Feet
To determine your material needs using a cement calculator in feet, you must ensure all your measurements match. The biggest mistake DIYers make is multiplying Length (in feet) by Width (in feet) by Thickness (in inches).
Always convert your thickness into feet first! If you are pouring a 4-inch slab, divide 4 by 12 to get 0.33 feet. Then, multiply Length × Width × 0.33 to find your total volume in Cubic Feet.
Once you have your cubic feet, using a cement calculator bags tool is easy. Because one 80lb bag of pre-mixed concrete yields exactly 0.60 cubic feet, you simply divide your total cubic feet by 0.60 to find your exact bag count.
Portland Cement Calculator (Mixing from Scratch)
If you are a contractor mixing your own concrete from scratch (rather than buying pre-mixed bags), you need a true Portland cement calculator.
The standard concrete mixing ratio is 1 part Portland cement, 2 parts sand, and 3 parts gravel (by volume).
To produce one full cubic yard of standard 3000 PSI concrete from scratch, you will need approximately:
- Portland Cement: Five 94lb bags (470 lbs total)
- Sand: 1,400 lbs (roughly 0.5 cubic yards)
- Gravel: 1,800 lbs (roughly 0.75 cubic yards)
- Water: 25 to 30 gallons